Testing system



Nov.A 30 192,6.

H. W. MaCDOUGALL TESTING SYSTEM Nov. 30 1926.

H. w. MacDouc-:ALL

Nov. 30,1926'. K 1,608,516

H. W. MaCDOUGALL TESTING SYSTEM Filed Nov. 19. 1924 5 Sheets-Sheet 3 Nov. 30 1926.

H. w MacDoUGALL TESTING SYSTEM Filed Nov. 19, 1924 5 Sheets-Sheet 4 [IUDDUUUDUUDUIIU E UBUUUUU B Aff'y.

H. w. MaCDQUGALL TESTING SYSTEM FilediNv. 19. 1924 5 Sheetsheet 5 lll Patented Nov. 3), 1926.

llllillll?. STATES tisane PATENT oiriii.

HARRY V. MAGDOUGALL, 0F EAST ORANGE, NEV JERSEY, ASSIGNOR TO 'WESTERN ELECTRC CMPANY, .'NCDRPURATED. NE'W YORK.

'rasante sYsaniu.

Application iiled November Vihis invention relates to testing; systems and niore part. cularly to an arrangement for testing apparatus einployed in a machine switching telephone systen'i 'for producing iinpulses. rl'his application is a continuation in part o'j my co-pending application Serial No. 599,204, filed lloveniber 6, 1922.

ln machine switching telephone systems of the panel type such as disclosed in Patent No. 1,395,977, to i A. Stearnet al., of Noveinher l, 192i, and in Patent No. 1,501,871, to F. ifi. Stearii of Julyv l5, 1921i, iinpulse inachiiies are einployed tor transinitting,l impulses used in setting` the register relays in the sender circuit. For convenience of Adisclosure, the iinpulse inachine described in seing patents comprises a druin oit u7u inaterial in which a plurality olf circumferential rows oi' contact segments are embedded, these segments being connected to a source oil current through a coinn'ion slip ring. A plurality of brushes eneje the several rows et segments and are fngied to be variously connected to the Vcontacts oit the banks of translator switches through suitable distributing` bloelrs `for conducting inipulses of current troni the several Contact segments to the banl termina-ls of the translator switches. ln actual practice, however, the inipulse machines employed consist oi two groups et' circular drums or connnutators each druin having one or niore metallic Contact segments on its periphery. rlhese drunis are inounted adjacent to each other ou a rotatable shaft, the snaitfts being continuously driven by any suitable source of power. .individual to each drum is a lr amig the segments of its assol 1"" s rotation.

ses transmitted by the to be oi the proper charthere is an open circuit "i should be closed, or iii the @nient and its as- 1 lied inaniinuni, ahoy, which the particular circuit will not failure in the connection will the invention'is to `guard inst such failures by providing' an arianuenient lor automatically testing` the p lee inachiiie under lconditions similar to this@ tound in actual use.

lt), 1924;. Serial N0. 750,752.

nient whereby a plurality oit druins are automatically tested in succession a predeterinined nuinber et' tinies. y

Another feature of the invention is an arrangement whereby two pgiou is of drunis are alternately tested autoinatically and the testing operation stopped aiter a predetermined nuinber ot tests has been inade.

.another feature Ot the invention is an arrangement for repeated y testing any desired one ot these drums during a routine test.

Another feature of the invention is an arrangement whereby the continuity of a circuit through the testing` device will be broken and progression arrested it two brushes become short circuit/ed or the nonconducting portion et the druin surice becoines conducting by reason olf a substance short-circuited with the conducting portion et said druin.

A further feature resides in the provision of two groups of relays responsive to iinpulses frein the druins et the pulse inachine under test which are ditlferently adjusted `and are used alternately to ehecl; the circuits through tl .e druins whereby different test conditions are iniposed on the druins.

Another ieature the invention is an arrangement for stopping; the test and actuating a visible and audible signal it a failure occurs.

Another feature oi the invention is the provision ot a hey 'l-or restoring the apparatus to norinal atter a failure has caused the apparatus to stop oil1 norinal.

lt is thought that the invention will best be understood j'froni the followingl description, reference being` had to the accompanying drawings which when italien together should he placed as shown in Fig. 6 to illustrate the invention.

Fig. l shows terininal banks el: switches l) and ,l5 and associated i'zestinnl eipiipinent for successively testing druins o'l' pulse inan chine group i or B alone; with relays for associating the terminal banks and testing equipment et this ligure and Fig. 23 with vpulse machine group A.

Fig'. 2 shows in developed forni` the l group oi' drums ot a pulse inachine under test, a sequence switch` shown to the right of the dot and dash line for successively vselecting'drumsof the A group, a portion of a master sequence switch shown at the left ot the dot and dash line which functions with the other sequence switch of Fig. 2 and the sequence switch ot Fig. l to select drums of either the A or B groups, and lamps for indicating the particular group o't drums and the particular drum in the group which has been selected.

Fig. 3 shows terminal banks and control mechanism tor switches D and E and associated testing equipment :tor successively testing drums of pulse machine group A. or .5 along` with relays for associating the terminal banhs and testing equipment of this ligure and Fig. 1 with pulse machine group B.

L1 shows 1n developed torni the P group ot drums o1" a pulse machine under test, a sequence switch shown to the right ot the dot and dash line ior successively selecting the drums of the B group, and the remaining cams ot' the master sequence switch shown in Fig. 2.

5 shows a counting switch, counting relays and other control equipment for the testing device.

cscrz'ptz'oa of apparatus.

in Figs. 1 and 3 are shown two switches E and D used in conjunction with the register relays inmediately to the right thereof tor providing checking paths tor each of the l0 drums. Each switch serves in the test oit' twenty drums ot a pulse machine and therefore, two switches are required to test all ot the drums. rihe D switch tirst traverses its terminals 'for testing the first twenty drums and rests on terminal 21 while the E switch passes over its terminals to test the next twenty. Relays 10G, 107, 10S, sce, so?, ses, iis, ne, isc, sie, :ne and aso are register relays which operate in connection with the receiving drun'is ot the pulse machine, and with the switches D and E. "hese relays are similar to the corresponding register relays ot a standard sender with vthe exception that one set has a weaker ad- `inst-ment and the other a stronger adjustment than the sender register relays. The above mentioned switches, and the counting switch C ot 5. arc ot the well known step-byestep type wherein the brushes being adapted to be moved upon the deenergization et their respective stepping magnets 617, 302 and 303.

Sequence switches 210, 220 and Ll1() which are shown in Figs. 2 and s are similar to the one described in detail in the patent to Reynolds and Baldwin No. 1,127,808 of February 9, 1915.

To the lett of the dotted line Fig. 2 and Fig. l is shown sequence switch 210. rlhis switch moves one position for each sending drum tested and when live tests have been made moves sequence switch 220 or 410, de-

pending upon which group of drums is being tested, one position to connect the next group ot tive drums. l/Vhen ten drums S-1 to SM10 have been tested, sequence switch 21() restores to normal, in which position ten other drums S-ll to S-20 are tested. Sequence switch 210 maires tour revolutions to test the d() drums. ln position 2 to 11 ot sequence switch 22() drums S-O, S-l, S-2, S-S and S-t are con nected through positions 1, 2, 8, 4, and 5 respectiif'ely ol sequence switch 210. From position 3 or 12 ot' sequence switch 220, switch drums SM5, 5 6, S-T, ifi-8, and ,5S-9 are connected through positions t3, 7, S, 9 and 1t) ot sequence switch 210 and so on. Sequence switch 220 moves one position for each tive drums tested. Fig. #i shows the B group oit' drums which is similar in all respects to the A group ol.l Fig. 2. Sequence switch 410 shown in Fig. el, is used in the same manner sequence switch 22() for testing the B group. rlhe impulse machine which is shown in its developed torni in the right hand portion ot Figs. 2 and Ll coinprises two groups ot drums designated A and B respectiifely, comprising' a group o't sending drums S, a group oit receiving drums ll. and a timing drum T. The section included by the parentheses R and R are the receiving drums, the segments T and T are the timing drums and the remaining drums included within the parentheses S and S are the sending drums. Battery is continuously connected through brushes 2911L and 491i to rings 293 and rilhe drums are assumed to rotate in the direction indicated by the arrow.

yThe block DB shown on both F 2 and t is a cross connection block for cross connecting the brushes o the impulse machine to the cams otl sequence switchds and 1110 and to baul-z contacts of sender translator switcher-s. Fie'. 2 also shows three series oi lamps for indicating to the test man the particuhzr group and the number ot the sending drum b1' t Lamps j; and

rested. B are alternately lighted to indicate the Progress group ot drums being tested. lamps (l to indicate the tens digit et' the drum number being tested and lamps O to 9 indicate the unit digit ot the drum number being tested. It sending drum tlg-21 ot group A is being tested circuits are closed for lighting lamp A. tens lamp 2 and units lamp 1. rlhe counting switch C sh Fig. `5 is controlled by magnet 517 used to count the cycles or" the test. switch taires one step for each complete test of the groups ot drums i and B. `il'hen 20 complete tests have been made which is indicated by the switch stopping on terminal 22 the relay 502 is operated stopping the testand restoring all apparatus to normal.

Fig. also shows a return to normal key lll) isc

f device.

,andere 503 which restores all equipment :to-.normal at any tiine during the test. A repeat key 507 is also shown 'in Fig.` 5. This `key is operated to advance the circuit to a particularcruin on which a 'series ot test-sare to he inade. ln case oi failure ot a drum and it is desired to repeat 'the test, hey i307 `is operated in conjunction with hey 510 which is the control advance key. This key is used `for advancing` the test circuit troni a blocked position in order to start theneiat test. Key 501 is a start key W iich is used .for starting `the test circuit on its cycle ot tests.

The gang switches G and G shown on ldigs. 2 and l are employed to connect any one ot a plurality `of pulse machines into service or into association with theletesting bis disclosed the ,pulse machine il luetrated is connected over the upper conde- VIn ,order tov more casi-ly understand: :the operation of `the test circuit, it will he as- -suined that the test circuit taires the place of `a send r, 1n which case the pulses 'troni the `sending cli-unis prepare circuits Whichextend througha vcoinhiinition ot relays similar to the register relays or the sender kand thence throught() the receivingdrunis. Certain ot these register relays are operated according to the denoininationfot the `ipulses sent. Should any or all of `these relays tail to operate either hy reason of a `short or open circuitorground, a circuit will not the coin pleted through to the ,receiving i drums. Should-this be the case, a circuit is not coin- `plated for advancing` `the testing' device to its next test position. lWhen `this occurs, a circuit is closed for lighting` a lainp und operating a bellas `a signal to the test inan oroperator that there is aftailure upon said drum. Upon thefahove mentioned failure, the test incan, hy noting' thefnuinher ot` the `drurn indicated bythe lamps, inay ettect, a repair and thus continue the test. It it is desired -to repeat the testy of this particular dru1n,.a lrey is operated, causingthe .test circuit to repeat the test of the repaired druin -so `longue the operation of the .key is continued. It, onthe other hand,v it Vis desired to return the circuit to normal after aV tailure, another key is operated whereupon a new set of tests is initiated.

Description of operation.

` "Testing drums-0f the A groups-#To start the test the test inan'operates"lrey501 which closesa circuit Afor 'operatingrelay 301 troni hattery,tlirough its Winding, conductor upper inalre contact of ,key 501, conductor -530 to lett' hand contacts ofsequence' switch springAtOl, conductor LL25, `lower contactsolI sequence switchsprings 201 fand'j202, con- `-gdueter'2215 tojgroun'd onthelower makefcon.-

tact -ofE lrey 501. "*R'elayl locks* fromsbat- Contact of lrey alay 514 nonT operates ov tnery, 'through iront contact, or relay "502 to S, conductor 22K-right outer front contact oi relay 301, conductor 340, lower contacts ot sequence switch springs $02 and ltl to ground. In position 2 a circuit closed for lightinglainp A from battery through resistance 298, lainp A to ground on the lower ,right Contact otsequence switch cani `207', indicating that the A group of druins is being tested. Switch D now nieves elil norinal to position 1, magnet 302 being energized over a circuit t'roin battery, through its Winding, conductor haci: contact of relay 101, conductor 121, right outer hack contact oi' relay 506, conductor 532, upper hach Contact hey 50T, conductor 533, hack contacts of magnets 302 l andBOS, conductors 320, and 327, right hack contact of relay 102, outermost right haclr contact or relay 103, conductor inner- .inost upper hack contact of lrey 503, conductor 534, terminal 22 and brush ot arc 112, conductor 123 to ,ground on che upper contacts of sequence switch springl 202. Re

' a circuit troni battery, on the lett hack contact of relau 508, `conductor 534;, upper contact oit sequence kswitch spring 40a, conductor so, through the lett winding oit relay S1/l to the uppermost lower back contact oi"- key 503, conductor 535 to terminal 1 and hrush ot arc 112, conductor 128 to ground on the upper contacts ot sequence switch spring;` 202. The stepping relay 500 nonT operates and releases on battery pulses from pulsing,r segments T of the A group of drums over 1a "circuit from battery, hrush 29a, see;- unent 293 and T segments on druin A, `brush 250, contact ot sequence switch sp1-ine; 204;, conductor 226, innermost right haelt contact of relay 804, conductor 328., through the Winding ot relay 509, innermost lett back contact of relay 540, conductors `and 537, outerinostleit haelt contact ol relayg514, right hach contact oi relay S, eonductor 538, upper, Contact ot sequencesiritch sprin'gr206 to ground en the upper Contact ot' sequence switch spring 207.

ing of relay 511, conductor 540, lower contact oft sequence switch spring 424, conductor 534, to battery on the lett back contact of relay 508. lNhen relay 509 releases between the irst and second pulses a relay operates in series with relay 511 in a circuit trom battery at the lett back contact ot relay 503, conductor 534, lower contact ot sequence switch spring 424, conductor 540, through the winding ot relays 511 and 512, front contact of relay 511, conductor 536, con-- ductor 537 outer lett front contact ot relay A514, right back contact ot relay 503, conductor 533, upper right contact ot sequence switch spring 206, to ground through the upper lett contact ot sequence switch spring 207.

Relay 513 now operates from battery on the diti'erent sending drums through con-A tacts ot springs 222, 223 and 224, over conductor 246, outermost right back contact of relay 304, conductor 329, innermost upper Contact oit relay 305, conductor 510, through `the winding et relay 513, right liront contact ot' relay 512, outermost lett baclr contact ot relay 546, conductor 536, lett trent contact ot relay 514, right bacl: contact ot relay 508, conductor 533 to ground on sequence svitch spring 209. Battery on the S-O contact ot drum A, operates relay 513 over a circuit trom contact 229, brush 275, upper lett contact et sequence switch spring 236, lower contact ot spring 213, lower lett contact of sequence switch spring 223, conductor 246, outermost right baclr contact of relay 304, conductor 329, innermost upper back contact ot relay 305, conductor 510,

through the winding otl relay 513, conductor 515, right trent contact of relay 512, outer lett back contact ot relay 546, conductor 536, conductor 537, outermost lett trout contact ot relay 514, right back contact ot relay 508, conductor 533, upper contact ot sequence switch spring 206, to ground through the upper contact ot sequence switch spring 207. At this time a circuit is closed trom battery through units lamp 0 upper rignt contact ot sequence switch spring 121, lower right Contact ot sequence switch spring 212 to ground lighting lamp 0. A circuit is also established to light the tens lamp 0 trom battery through resistance 277, filament of tens lamp 0, to ground through the right upper contact ot spring 296. As hereinbetore described lamp A is lighted at this time to indicate a test ot the A group drums. This with lamp 0 and 0 indicated to the test man that the S--O segment of drum A. is being tested. The succeeding operations ot' relay 509 operate the counting relays 561 to 566, inclusive, according to the number ot pulses sent out by the pulse machine, in-conjunction with counting relays 541 to 546, inclusive. Since the pulse machine is designed to transmit six impulses per revolution these relays will all be operated during a single revolution ot the pulse machine and thus upon the operation ot relay 546 a complete revolution will be measured.

Simultaneously, relay 513 is subjected t0 pulses from the segments ot the sending drums under test, causing relay 513 to operate tor each segment encountered. Since the drum S-O under test at this time has but one segment, the operation et relay' 513 operates relay 105 once during a revolution ot the pulse machineV in a circuit from battery through its winding, conductor 124, innermost lett back contact ot relay 304, conductor 366 to ground on the contact ot relay 513. The operation ot' relay 105 connects the six conductors, 133 to 143, inclusive, which are connected to the receiving brushes 240 to 245, inclusive through the register relays 106, 107, 103, 306, 307 and 303. These register relays receive but one battery impulse each during a single revolution of the pulse machine from the R segments ot drum A. rlhus since relay 105 is energized at the instant the brush 240 engages the tirst receiving drum segment, this segment being in axial alignment with the segment 229 ot the S-O sending drum, a circuit is completed tor operating register relay 106, extending trom battery on the receiving drum segment, brush 240, conductor 143, uppermost contact ot relay 105, upper normal contact ot relay 104, lett winding ot relay 106 to ground. Relay 106 operates locking over its right winding and back contact ot relay 113 and its own front contact in parallel with relay 115 over conductor 146 to ground as previously traced at spring 207. As soon as the pulse machine rotates to disengage brushes 240 and 275 relays 513 and 105 deenergize. Wvhen the brushes 241 to 245 engage their respective R segments during the continued rotation ot the pulse machine, since there are no corresponding sending segments on the drum S-O and relay 105 does not energize, circuits tor the remaining register relays 107, 103, 306, 307 and 308 are not etlective. l/Vhen the pulse machine completes a revolution and relay 546 energizes, the circuit previously traced through relay 513 is rendered ineffective.

Uieolcz'ng the registration-Relay 546, upon operation, closes a checking path when relays 106, 107, 103, 306, 307 and 303 are correctly operated tor advancing the test circuit to the nent drum. Relay 506 operates in this checking path trom battery through its winding, conductor 547, right front contact ot relayl 546, conductor 543, lett back Contact ot relay 317, conductor 330, termi nal 1 and brush ot arc 314, conductor 335, back Contact ot relay 316, conductor 331, terminal 1 and brush ot arc 313, conductor 334,

.bach contact ot relay 315, conductor 332,

terminal 1l and brush ot arc 312, conductor 333, back contact of relay 117, conductor 130,

terminal 1 and brush. of arc 114,A conductor' 134, -baclr Contact of relay 116, conductor 131, terminal 1 and brush of `are 113, conductor 133, front Contact ot relay 115, conductor 135, terminal 1 and brush of are 112, conductor 123 to ground through the upper lett contact of cani 202. Relay 506, upon operating, starts the operations necessary `toadvance the circuit i'or testingfthe next drum.

rlhe operation ot relay 506 closes a circuit :tor operating relay 321 troni battery through its ,vinding, conductor 553, innermost left trent contact of relay 506, conductor 827, conductor 326, normal contacts of magnets 302 and 303, conductor 533, upper normal Contact ot hey 507, conductor 532, outermost right front contact oi2 relay 506, conductor 536, upper right contact of sequence switch spring 206 to ground on theupper lett contact ot sequence switch spring 207. Relay 321 closes a circuit through the Winding` of relay 322, right contact ot relay 321, conductor 350 to ground at key 516. `ground on sequence switch spring 207, however, shunts relay 322, until magnet 802 breaks its contact. Magnet 302 is nour ener-4 gized in a circuit from battery through its Winding, conductor 325, right back contact of rela-y 101, conductor 121, conductor 354, outermost lett iront Contact of relay 321., conductor 355, conductor 538 to ground through the upper lett Contact of sequence switch spring 207. rllhis operation of magnet 302 removes the shunt from around relay 322, allowing it to operate from battery through its Winding, right front contactoi relay 321, conductor 350 to ground on:I the uppermost Contact ot key 516. Relay 821 nouvl locks through its innermost left front contact to ground overconductor 53S as pre viously traced. Magnet 302 remains operated until sequence switch 210 mov s into position 2. rlhe operation o'l relay ad,-

vances sequence switch 210 'trein position 1 to position 2 over a circuit troni battery through sequence switch magnet 210, lower mains in position 2.fthereby closingv circuits tor vthe test ot sending drum SL41.

lliith switch D in position 2 relay 514 operates over the saine circuit as traced above. The counting relays operate as the pulse machine rotates, land relavsj513- and operate- When. the brush 283 engages seg-ments of drum S-fl, thus closing the tionlot relay 106 closes a circuitl for the operation ot relay from battery through its \vihding,.leit :tront contact of relay 106, conductor 146', outerniost lett front Contact oty relay 514, right back contact of relay 508, conductor to ground on the lower left contact ot .sequence switch spring 209. The Yoperation of relay 10S closes a similar circuit tor the operation of relay 117. Relay 106`operates in a circuit :troni ground through its lett Winding, conductor 147, uppermost lower back contact. of relay 104, innermost upper front Contact ot relay 105, conductor 141, brush to batteryon the third segment 01"' section R ot drurn A. After relays 541 to 546 and .361 to 506 have been operated. as hereinbetore described, the checkin'geircuit will be closed i'or operating relay 506 in a circuit from battery through itswinding, conductor 541/', right front contact of relay 546, conductor 54S, back contact of relay 317, con and brrufh or" are conductor 335, baci-z contact ot relay 310, conductor 831, termif nal 2 and brush oi arc 813, conductor 334 bacl 'contactotl relay 315, conductor A332, terminal 2 andbrush ot are 312, conductor 3233, trent contact et relay 11'?, conductor 137 terminal 2 and` brush of are 114, conductor 134, baclf: contactot relay 116, conductor 131 terminal 2 and brush' of are 113, oondinftor fr( Contact of relay 115, conductor 135, terminal2 and brush of arc 112,` conductor12f` to ground through the upper contacts et sequence 'switch .spring 202. Sending segments S-2, 5 3 and 5 4 are tested in a similar manner havthrough front contacts of relay 117, of relays 116., and 1.1i', and relays 115 and` 116 respectively. Sequence sivitch 210 ad` post" t each drum tested varices one until pes scenic-n lVith sequence switch in position 2 it is only possible to test segment-s S-0 to .lherefore, it will be necessary to advance the switch into position 3 for testing segments to Ffa-49. ISefpience switch is advanced to position 3 in a` circuit from battery through" sequence switch magnet 220, upper lett contact of" sequence .switch spring 208. conductor 254 to ground on the upper lett Contact oli se quence svitch spring 209.` rthe test circuit. duringthis period, 's prevented from mal;- ing aV test by op iiiig the ground on sequence switch sprin 207. lWhen position 3 reached, L.fonts to Ein-9 inclue sire.y are testetl .in a similar manner `to segr# niente Sil-0 to hitter segment SWS hart. veen tested. to position 11 by the checking. path asihereductor 330, terminal 2` 'l seuuence switch 210 is moved nr unl inbetore described. As'position 11 is a pass by position, the sequence switch is moved to position 12 over a circuit from ground through the upper Contact of sequence switch spring 212, upper right contact ot sequence switch spring 211, to battery through sequence switch magnet 210. Position 12 is also a pass by position and the switch is moved to position 13 over a circuit from ground through the upper right and lower lett contacts ot sequence switch spring 203, conductor 29a, lower right contact ot sequence switch spring 211 to battery through the winding of sequence switch magnet 210. Sequence switch 210 is moved to position 14 by ground on its master contact. Sequence switch 210 is now moved into position 15 over a circuit Jfrom ground through the upper lett contact ot sequence switch spring e112, conductor 1116, upper contacts oit sequence switch spring 201 to battery through the winding ot sequence switch magnet 210. The sequence switch is now advanced through positions 16, 17 and 13 and into normal position 1 by its master contact. When sequence switch 210 reaches position 1, sequence switch 220 moves from position 3 to position l1 over a circuit from ground through they upper right contact of sequence switch spring 209, conductor 2113, lower left contact ont sequence switch spring 208 to battery through the winding oi sequence switch magnet 220. The testing circuit is now in position 'for testing segments S-10 to S-14- lVith sequence switch 220 in position L1 and sequence switch 210 advanced progressively through positions 1 to 5, drums S-lO to S-lli are successively tested. Sequence switch 220 then advances to position 5 and as sequence switch 210 advances through positions 6 to 10, drums S-15 to S-19, inclusive, are tested in a similar manner to that tor testing drums 5 0 to S-9, hereinbeiiore described. At the termination et the test of drum 2a-19, sequence switch 210 advances to position 11 over the circuit described above and allows the switch D to step to terminal 21 where it remains during the test ot drums S-20 to @1 -39, inclusive.

At this time, relay 101 operates in a circuit from battery through its right winding, innermost right back contact ot relay 103, conductor 155 terminal 21 and brush of are 112, conductor 123 to ground through the upper contacts of sequence switch spring 202. rllhe operation ont the relay 101 closes circuit for starting the switch E. This circuit may be traced from battery through magnet 303, conductor 356, right front contact of relay 101, conductor 121, outermost right baclr contact of relay 506, conductor i 532, upper normal contact of key 507, conductor 533, interrupter contacts of magnets 302 and 303, conductor 326, conductor 327, right baclr contact of relay 102, conductor 156, normal terminal and brush of arc 109, conductor 152, conductor 159, outermost lett front contact ot' relay 101, conductor 123 to ground at the upper contacts of sequence switch spring 202. This circuit moves the switch E from its normal position to position 1 in which position segment tl-20 may be checked.

` Sequence switches 210 and 220 now advance for testing segments `S--20 to S-29 in the same manner as described for testing seg ments (5-0 to vs -0. lfhen sequence switch 210 leaves position 10 ai'ter two complete revolutions, the E switch is now on terminal 21. At this time relay 102 is operated over circuit from battery through its winding, conductor 153, terminal 21 and brush ot arc 102, conductor 152, conductor 159, outermost left front contact of relay 101, couductor 123 to ground at the uppercontacts ot sequence switch spring 202. Relay 101 now locks to ground in parallel with relay 102 through its lett winding and innermost left front contact conductor 160, conductor 158, terminal 21 and brush of arc 109, conductor 152 to ground on the innermost lett front contact oik relay 102. Relay 103 now operates ina circuitfrom ground on the outermost left 'front contact of relay 102 and locks through its right winding and innermost right front contact, conductor 155, terminal 21 and brush of arc 112, conductor 123 to ground through the upper contacts ont sequence switch spring 202. rlhe brushes of the switch E are moved to normal at this time over a circuit from battery through magnet 303, conductor 356, right trent contact of relay 101, conductor 121, outermost right baclr contact ol' relay 506, conductor 532, upper contact o1c lrey 50T, conductor 533, normal contacts ot stepping magnetsv302 and 303, conductor 326, conductor 327, right front contact of relay 102, conductor 158, terminal 21 and brush of arc 109, conductor 152, conductor 159, outermost lett trent contact ot relay 101 to ground ou the lett Jfront contact o'i relay 103. When terminal 21 ot the switch E is passed, relay.v 102 is released. Relay 101 was held operated in parallel with relay 1.02 in order to step the switch E to normal. When relayY 102 releases, relay 101 also releases closing a circuit for stepping magnet 302 ot switch D from battery through magnet 302, conductor 325, right bach contact of relay 101, conductor 121, outermost right back contact or' relay 506, upper normal contact of lrey T, conductor 533, through the normal contacts oi' magnets 302 and 303, conductor 326, conductor 327, right back contact ot relay 102, outermost right front contact of relay 103, conductor 155, terminal 21 and brush of arc 112, conductor 123 to ground on the left front contact of relay 103. Relay 103 releases'when terminal 210i arc 112 et the l ift-il switch l) is passed. rllhe circuit is not? in condition ior testing the B group'oif drums.

1idilio-,ii drum T52-i0 of the i group is tested, sequence switch 210 moves to position 11 over the checking path. 1n position 11 ot sequence switch 210, sequence switch 220-is restored to normal position 10 over a circuit from battery through sequence switch magnet 220 lower right contact of sequence sivitch spring Q08, conductor 29e to ground on the upper left contact ot sequence switch spring Sequence switch 210 non' moves to position 12 over a circuit hereinhefore traced to ground on sequence switch spring ln position 12 of sequence switch 210, semence switch 110 is moved oii normal ver a circuit trom battery through sequence switch i'nagnet 110. lower right contact yoit' sequence switch spring' 111, conductor 1;91, upper contacts oi? sequence switch spring 410i?7 conductor l105 to ground through the louter lett contact ot sequence switch spring 212.. Sequence switch 210 now moves out of position 12 over a circuit 'from battery through iii-cnet 210. lower right cont-act of sequence switch spring 211, conductor 127, to ground tnrough the upper right contact oi sequence switch spring 112. As position 13 ot sequence switch 210 is a pass hy position the switch is moved by ground on the master Contact of the sequence switch magnet to position 111. rlhe switch is moved out of position 111 over' a circuit from battery through the Winding of sequence switch magnet 210, upper contacts of sequence switch spring 201, conductor 1146 to ground through the upper lett contact ot sequence suitch spring 112. Sequence switch 210 is advancet` through positions 15, 16, 17 and 18 hy ground on the master contact oil the sequence switch. l/llith sequence switch 410 advanced to posit-ion 2 a circuit is estalilished for the transfer relay 304i from battery through this relay, conductor 357, to ground at the upper lett contact of sequence switch spr u' L103. The operation oil relay 3011 suhstl relay 0.7553 for relay 105 for connectthe receiving drums oi the B group rather than the receiving` drums oit the A up 'to the resister relays.. and transfers control conductors 328 and 320 to springs ot sequence switch 110 rath-cr than to springs ot sivitch 220. Then sequence switch 210 reaches position 1, a circuit is then completed for 'testing drums Ei-O oi' the B group. lrushes 1150to 190, inclusive, are connected through earn of sequence switch 110 to the test circhi and the regis-` ter relays oi' the test circuit to the brushes to l1/5, inclusive, which engage the drums oit section R ot the pulse machine. l'- 1shes 1:20 to 4100, inclusive., en@ the drums S o't drum B.

The test of the B group of drums proceeds exactly as described for the A' group of drums with the exception that relay 323 is used in place ot relay 105 until sequence switch 4110 reaches position 0 and sequence switch 210 reaches position 11, at which time magnet 517 is energized in a circuit from battery through the magnet, terminal 1 and brush 'or' arc 521, conductor 559. inner lett front contact et relay 50e, conductor 560, upper contacts ot' sequence switch, spring 413, conductor 1192, lower left contact ot sequence switch spring 411.0 to ground. ldfhen sequence switch 210 advances past position `15,fn'iagnet 517 deenergizes and steps switch C one terminal to register a complete test of the le and E groups o't drums.

icconcl est of A group of ruina-Sequence switch Q10 moves out of position' 1 1 in a circuit from battery through sequence switch magnet 2107 upper right contact oit sequence switch spring 211 to ground at the upper contact 01"' sequence switch spring 212. 1t moves from position 1Q into position 13 over a circuit 'from battery, sequence switch magnet 210, lower right Contact oit sequence switch spring 211, conductor Ll2?, to ground through the upper right contact of sequence switch spring 112. moves to position 1t under control ot ground on its master contact. ln positions 14: ot sequence switch 210, sequence switch 410 restored to normal in a circuit from battery through sequence switch magnet 410, contacts of sequence switch spring 101j conductor 290, lower right Contact ot sequence switch spring 213 to ground.V Sequence switch 210 moves out of position 111 in a circuit from battery through its magnet, upper contacts 01:' sequence switch spring 201, conductor e46, to ground through upper left Contact oi' sew quence switch spr" ig 112. Sequence switch 210 advances through positions 15, 16, 1T and 18 under control `ot its n'ias'ter contact. Relay 304 is now released transferring control baclt to relay 1055 and sequence switch 220 for associating the receiving and sending drums ot the A group with the 'testing device.

llith switch C in position 2 a circuit is established tor relay 1011 trom battery through the winding oli this relay, conductor u 1415 the No. 2 terminal and brush of arc 523. inner right trout Contact o1 relay 501 conductor 532m ground at the inner righi: liront contact ot start relay 501. Relay 305 is also energized at this time over a circuit extending from battery through its Winding. No. 2 terminal and hrush` ot arc ol? switch C to ground at the outer right :trout contact of relay 504. lllith relays 104 and 305 energized, conductors 138 to 1113 inclusive, are transferred through contacts o1' either relay 105 or 323 to the windings ot register relays 118, 119, 1207 318, 319i and 320, from thewvindings of register relays 1.06, 107, 108, 306, 307 and 308. l/Vhen relay operates relay 518 is substituted tor relay 513 so that during the second test o1" the pulse machine drums relay 518 operates in a circuit extending from the A group ot sending drums ot' the pulse machine over conductor 216, the outer right baclr cont-act ol" relay 304i, conductor 329, the innermost upper iront contact ot relay 305, conductor 'winding ot relay 518 thence as previo sly traced for operating relay 513. The reg iter relays 118, 119, 120, 318, 319 and 320, relay 518 and relay 105 operate to control relays 115, 116, 117, 315, 316 and 317 in the manner previously described for the control of these relays. Y

1t is to be noted in this connection that switch C advances one step after each complete test or" all of the drums of the pulse machine, it alternately renders the relays 513 and 518 and the two sets ot register relays available for the purpose ot applying different test conditions one setot register relays having a stit adjustment to fail on v. ,ali pulses and the other set having a weak adjustment to operate on *false pulses of any sort. This change is made alternately until the switch C reaches position 21. ln position 21. switch C is advanced automatically over the brush of arc 520 into position 22. 1n position 22, relay 502 is operated from battery through its incline, terminal 22 and brush or arc 522 to ground on the outer left front Contact oit relay 504i. The operation oit relay 502 opens the locking path for start relay 301, allowing relay 301 to release. rllhe release of relay a allows magnet 517 to restore the switch C to normal.

lt at any time during the test of either the il, or B groups o1 drums a condition arises whereby two adjacent brushes or drums are short circuited, an incorrect number of register relays will be operated causing the circuit to stop and light the signal lamp and operate the gong 527. For example, it brushes 274 and 275 should be bent tofeher or short circuited while the sequence 'itch 220 is in position 2 (which is the osition for testing drum @-0) .live impulses will be sent outl instead ot one thereby operating an incorrect number of the register u relays and relay 506 will remain unoperated thus operatng relay 526 which in turn lights the lamp 525 and operates relay 505 ringthe gong 527 a signal ot an unstandard condition.

Failure of drama-l1: at any time during any ot the tests oif the drums of groups A or incorrect registration is made, relay 506 will not operate and relay 526 is operated from battery through resistance to its winding, outermost le'lit 'front contact oit relay 506, outermost lett iront contact ot rclay 516, conductors 536 and 537, outermost lett front contact ot relay 514, right back contact ot relay 508, conductor 538, and to ground through springs 206, 207, 209 and 23 depending upon what drum ot the A or B group is under test and the consequent positions or' sequence switches 210, 220 and 410. The operation oit relay 526 closes a. circuit t'rom ground on its nalre contact through lamp 525 and winding ot relay 505 to battery. This circuit operates relay 505 and lights lamp 525. closed on the Jiront Contact oli' relay 505 for ringing gong 527, thus giving an audible and visible signal to the test man or operator that the test circuit has been blocked on account oi a failure, short or open cir.'V Should the timing leads or 3/19 'from the A or B groups ot' the pulse machine be open and therefore pick up relays 511 and 512 ifail to operate, relay 526 will operate in circuit from battery through its winding, innermost lett front Contact ot relay 511, conductor 554i-, back contact ot relay 511, conductor 536, conductor 537, outermost lett 'front contact of relay 51st, right back contact ot relay 508, conductor 538 to ground at springs of sequence switches 210, 220 and +110. rlhe operation ot relay 526 operates the alarm and lights the lamp as hereinbetore described. In order that the test man or operator may be able to determine the number of the drum and group upon which the failure has occurred, progress lamps are provided, progress lamps 0 to 3 being used ifor designating the tens digit of the number and lamps 0 to 9 being used to designate the units digit of the number. There are also provided lamps A and E tor designating the group of drums upon which the failure has occurred, lamp A designating the A group and lamp B designating the B group.

Repeat testa-The test on any individual drum may be repeated by operating key 50i' at the time when the circuit has progressed to the drum or after a failure. After relay 506 is operated to indicate correct registration instead ot advancing the test circuit. tor testing the next drum as previously doscribed, with itc); 507 operated. rel-aj.' 508 .is operated from battery, through its right winding, uppermost alternate contact ot lrey 507, conductor 532, outermost :front contact of relay 50G, conductor 538 to ground through springs of sequence switches 210, 220 or 4110. Relay 508 locks to ground trom battery, on its lett front contact through its left winding, right back contact oit relay 52st, lower alternate Contact of lrey 507, conductor 538 to ground through springs of sequence switches 210, 220 or 410. The operation ot relay 508 unlocks all ot the count ing relays 541 to 516 and 561 to 566 and any one or more ot relavs 106, 107. 108, 118, 11.9, 120, 306. 307, 308, 318, 319 or 320 which were operated on. the preceding test, in turn reln turn, a circuit is leasing relays 115, 116, 117, 315, 316 and 317 and relay 506. Vith key 507 operated when relay 506 operates, the circuit for relays 321 and 322, hereinbe'lfore traced is not etl'ective and therefore switches D, E and sequence switches 210, 220 and 410 do not advance to select another drum for test. Then 506 releases, relay 524 operates in a circuit `from battery at the left front contact of relay 508, through its winding, interinediatealternate contact of key 507, conductor 561 to ground at the innermost right back contact ot' relay 506. The operation of relay 524 releases relay 508. The release of relay 508 releases relay 524. The test is then repeated in a similar manner as hereinbetore described as long as key 507 is held operated.

Restoring a circuit to normal after Melara-When it is desired to restore the test circuit to normal, key 503 is operated. In this case, it is assumed that the failure has occurred on drum S-10 of the A group of drums. At this time, sequence switch 210 is in position 1. Sequence switch 220 is in position 4 and sequence switch 410 is normal. The switch D is in position 12 and the switch E is in normal position. Then key 503 is operated the circuit of relay 514 and the holding circuit of relay 301 are opened. Relay 514 upon releasing unlocks any operated counting relays, the release of relay 546 opening the circuit of relay 506. W' ith switch D assumed to be in position 12 a circuit is closed for stepping magnet 302 extending from battery, winding of relay 302, conductor 325, right back contact of relay 101, conductor 121, outer right back contact of relay 506, conductor 532, upper normal contact of key 507, conductor 533, normal contacts of magnets 302 and 303, conductor 326, right back contact of relay 102, outer right back contact of relay 103, conductor 122, innermost lower alternate contact of key 503, `conductor 535, terminal 12 and brush of arc 112, conductors 123 and 571 to ground at the upper alternate contact of key 503. Magnet 302 operates, opening its own circuit and advances the brushes of switch D to position 13. In position 13 a similar circuit is closed for magnet 302 eX- tending in this case from conductor 122 through the outermost lower alternate contact of key 503, conductor 570. terminal 13 and brush of arc 112 over conductor 571 to ground. Magnet 302 now advances switch D to position 14 and thence to normal over 'he two alternative circuits above traced,

The operation of kev 503 upon opening the circuit for relay 301` causes it to release and' connect ground over conductors 339, 341 and 254 for restoring any yot thev sequence switches 210, 220 or 410 `which at the time are oil normal to normal. The @i1- cuit fer restoring Sequence Switch 220 ertends from conductor 254 through the upper right contact of slziring 203, through the winding of magnet 220 to battery. Relay 301 also opens the locking circuit oi relay 504 which upon releasing closes a circuit from ground at its outer lett back contact, conductor 551, terminals and brush of arc 520 oi switch C, normal contact and wind ing oi' magnet 517 to battery. Magnet 517 energizing` in this circuit restores switch C to normal.

'When the switches C and D `have been restored and the sequence switches are in their normal positions all operated relays are released and the testing circuit is completely restored.

What is claimed is:

1. In a testing system for testing impulse producing apparatus, a testing device, a signal, and means for associating said testing device with said impulse producing apparatus, said testing device includingy means operative only if the impulses transmitted by said impulse producing apparatus are of an improper current strength, to actuate said signal.

2. In a testing system i'or testing an i1npulse producing apparatus comprising` a plurality oit commutators, each commutator having one or more metallic segments and plurality of brushes one for each commutae tor for completing circuits through said commutatore, a test device, and means in saiditest device to automatically and successively connect said commutatore with said test device.

3. In a testing system for testing an impulse producing apparatus comprising a plurality of commutatore, each having one or more metallic segments and a plurality oi brushes, one for each commutator for completing circuits through said commutatore, a testing device, and means to operate said testing device to automatically connect said commutators with said testingI device in fixed sequence.

4. `In a testing system for testing an impulse producing device comprising a plurality of commutators and a plurality of brushes, a testing device, a signal, and means :tor associating said testing device with said impulse producing device, said testing device including means operative, if the iinpulses transmitted by said impulse produc? ing device are of an improper character, to actuate .said signal.

5. In a testingO system for testing an impulse producing apparatus comprising a plurality of commutators, each con'iinutator having one or more metallic segments and a brush individual thereto, a testing device, 4a signal, means for associating said testing 'device with said impulse producing apparatus, said testing device including means for repeatedly testing the character of the impulses, and means tor actuating said signal it' the impulses transmitted by said apparatus are or an improper character.

6. ln a system toi: testing a series of' similar electrical devices, signals individual to said devices, testing means for said devices, means tor progressively associating said de vices with said testing means, and means tor automatically stopping the test when an unstandard device is tested and tor automatically displaying the signal corresponding thereto.

i". ln a testing system tor testing an iinpulse producing apparatus comprising a plurality of commutatore each having one orlmore metallic segments and a plurality t bi'fushes one for each cominutator for come plating circuits through said conn'nutators, a device, mea-iis tor successiyely con neet-ing commutatore with said testing device, land means for preventing the sucT cessive connection ot' said commutatore with said testing device and Vfor causing the ref peated connection ot any given commutator to said testing device.

8. ln' a testing system for testing an impulse machine having a plurality of' rotatable coininutators and a brush associated with each commutator, means to testsaid inachine for continuity ot circuit between said brushes and said commutatore under conditions similar to those which would be. encountered in actual practice, and means to automatically continue said testing operations a predetermined number oi" times.

9. ln a testing` system 'tor testing impulse machine having a plurality of rotatable commutatore and a brush associated with cach commutator, means to test said machine :tor continuity ot circuit between said brushes and said comimitators under conditions similar to those which `would be encountered in actual practice, means to automatically continue said testing operation a predetermined number ot times, a signal, and means to actuate said signal if an unstandard condition exists at the contacts of any brush and associated commutator.

l0. ln a testi-ng system tor testing an pui e machine-having a plurality of rotatable commutatore and brush associ-ated with eacli commutator, means to test said machine for continuity oft circuit between said brushes and said commutatore lunder the condition or la short' circuit between 'brushes or oominutator segments, a signal, and means to actuate:said `signa-l it saidfcon dition exists bett'veen said brushes,

il. ln a testing system tor testing pulse machine having a plurality of rotatable commutatore fand ja .brush associated with each commutator, :means to successively test said commutatore for continuity ot cirrendere' cuit between said commute-tors and said brushes under conditions similar to those'v Which would be found in actual practice,

means to lauto'matically continue said testing operation a predetermined number ot times, and means to repeat the test on any one ot the commutators of' said machine during the test.

l2. 'ln a testing system for testing an im-V pulse machine comprising` a plurality of groups of commutatore 'each commutator being provided with one or more metallic segments and a brush for each ot said commutatore, a testing device, means operating automatically to alternately associate the groups oi commutatore with the testi g dcvice, and means vfor'successively connecting the commutatore o the associated group with the testine' 'devicela a Destins 'S5/stein i'el testine es es nal-S@ machin@ G'elrfiaes .a plurality @if atours `Ot Commenter@ @edi Comunitat@ being provided Witl'i one or more metallic segments, and a brush tor each commutator tor engaging said metallic segments, a testH ing device, means' operating automatically to alternately associate the groups ot com mutators with the testing device, means to successivelyl connect the coinimitators ot the associated group with the testing apparatus, and signals :tor indicating which group 'ot commutators and which commutator ot the particular group is being tested.

let. ln a testing system for testing an impulse machine lcomprising a plurality ot groups and sub-groups oi commutatore each commutat'or being provided with one 'or more metallic segments and a brush tor each cominutator for engaging said metallic segments, a testing device, means operating automatically to alternately associate the groups and sub-groups ot commutators with the testing device, means to successivelyconnect the commutators of the associated group vwith the testing apparatus and sig nals for indicating -vvhich'group of commutatore and which commutator ci the partici ular group and sub-group is being tested.

1,5, ln aftesting system tor testing impi'ilse producing apparatus, a testing device, a signal, and means 'for associating said testing -device with said impulse producing dev e, 'saijd 'testing device including means op rati've, if the 'impulses 'transmitted by impulse ,ri-Odense @li-re@ er@ Of eil er character, to" actuate said signal Y utenti-'1e test in 'a testing system for testing an iinse ia@ eine haras a plurality re- 'table el- ,retailers and' e 'brine eeeecateel 1th each 0f .Seid .conmemora e means v tor establishing a vcircuit through Saidrfelev .endisaid ,0011i yiu-tators in' succs.. Sion, 'said relay 'being unresponglv@ .when

l Il

connected into circuit with a commutator which effects an open or high resistance contact with its brush, and a signal for indi-` cat-ing the unoperated condition ot said relay.

17. In a testing system for testing an impulse machine having a plurality of rotatable commutatore and a brush associated With each of said commutatore, a relay, means for establishing a circuit through said relay and certain of said commutatore in succession, said relay being unresponsive When connected in circuit with a commutator which effects an open or high resistance contact with its brush, a group of relays adapted to be variably operated over circuits controlled by said iirst relay and other of said commutatore, the relays oi said group being unresponsive when the commutators connected int-o circuit therewith effect open or high resistance contact with their brushes respectively, and a signal under the control otl said group ot relays for indieating an unstandard condition at any of said commutatore.

18. In a testing system i'or testing an impulse machine having a plurality of rotatable commutatore and a brush associated with each of said commutatore, a pair of relays, means for establishing a circuit through either of said relays and certain of said commutatore in succession, said relays being differently responsive to an unstandard condition at said commutatore and brushes, two groups ot' relays adapted to be variably operated over circuits controlled by said first relays and other of said conimutators, the relays of said groups being ditterently responsive to an unstandard condition at said other commutatore and brushes, a switch adapted to alternately select one of said iirst relays and one of said two groups of relays and a signal under control ot said two groups of relays tor indicating an unstandard condition of any ot said commutators.

19. In a testing system for testing an inipulse machine having a plurality ot rotatable commutators and a brush associated With each of said commutatore, a relay, means for .establishing a circuit through said relay and certain of said commutatore in succession, said relay being responsive When connected in circuit With a commutator which transmits a false impulse, a group of relays adapted to be variably operated over circuits controlled by said iirst relay and other of said commutatore, the

relays of said group being responsive when the commutator connected into circuit there with transmits a false impulse and a signal under the control of said group of relays for indicating an unstandard condition at any of said commutatore.

20. In a testing system ior testing an impulse machine comprising a plurality of rotatable commutatore and a brush associated With each of said commutatore, a plurality of relays, means i'or establishing circuits through a pair of said commutatore and a pair of said relays simultaneously, said relays being unresponsive when con-- nected into circuit with a commutator which elects an open circuit or high resistance contact with its associated brush, and a signal for indicating the unoperated condition of either of said relays.

In Witness whereof, I hereunto subscribe my name this 15th Iday ci? November A. D.,

HARRY W. MAGDOUGALL. 

